PRACTICAL 


SINFECTION 


CIRCULAR 

ISSUED  BY  THE 

I 

ILLINOIS  STATE  BOARD 
OF  HEALTH 


19  0 6 


SECOND  REVISED  EDITION 


SPRINGFIELD: 

Illinois  State  Journal  Co.,  State  Printers 
igo6 


NOTE. 


The  disinfection  of  infected  premises  is  as  important  as  the  main- 
tenance of  a quarantine  during  the  prevalence  of  the  disease.  The 
virus  of  contagious  and  infectious  diseases  will  often  live  for  years. 
It  is  imperative,  therefore,  that  the  infected  premises,  with  its  con- 
tents, be  thoroughly  disinfected  immediately  after  the  death  or  re- 
covery of  the  patient,  in  order  to  avoid  a spread  of  the  disease. 

A disinfection  performed  in  the  manner  recommended  in  this  cir- 
cular, will  be  thoroughly  eflPective.  The  work,  however,  must  be 
properly  done,  as  directed,  else  the  disease  may  remain  in  the  house, 
a menace  to  the  health  and  lives  of  those  who  enter.  The  health 
officer  should  never  forget  the  fearful  consequences  which  may  follow 
a neglect  in  any  particular  of  this  important  duty. 

Disinfection  should  be  performed  by  the  city,  village,  township 
or  county  authority — (the  latter  in  counties  not  under  township  or- 
ganization only — in  territory  outside  of  cities  and  villages) — under 
the  immediate  direction  of  or  by  a qualified  health  officer,  or  physi- 
cian or  embalmer  licensed  by  the  State  Board  of  Health. 

“ Whatever  measures  are  adopted  should  be  made  thorough. 

“Measures,  good  or  bad,  half  done  are  worse  than  useless,  as 
they  give  a fancied  security.” 


CONTENTS. 


PAtJES 


General  considerations— Object  of  disinfection- 
. —What  would  be  an  ideal  disinfectant 


-Disinfection  of  premises  during  illness 


I 


Aerial  disinfection— Rules— Preparation  of  room  and  contents— Subsequent  disinfection 
—Insecticides,  formaldehyde  and  sulphur 

Sulphur  disinfection— Rules— Plxperiments  of  State  Board  of  Health— Disadvantages  of 
sulphur— When  sulphur  is  dependable 


5-6 


7-8 


9-10 


Formaldehyde  disinfection— Methods— Experiments  in  past  years  w’ith  lamps  and  gen- 
erators—Experiments  of  State  Board  of  Health  1898-1902— Formaldehyde  sprinlcled 
on  blankets  and  sheets— “Sheet  method”— Generators  and  autoclaves— “Candles”— 
Breslau  method— Modification  of  Breslau  method  recommended  under  certain  con- 
ditions—Best  formaldehyde  necessary— Much  poor  formaldehyde  on  market 


11-14 


P'1 


Formaldehyde  and  potassium  permanganate  method  of  generating  formaldehyde— The 
method  recommended— Rules— Apparatus— Quantities  of  chemicals— Best  quality  of 
formaldehyde  necessary;  price— Account  of  experiments  at  ordinary  temperatures— 
Penetrating  power 15-21 


Formaldehyde  and  potassium  permanganate  method— The  method  recommended— Re- 
sults at  low  temperatures— Previous  experiments  at  temperatures  below  60°— Ac- 
counts of  experiments— Methods  subjected  to  the  severest  tests— Freshly  dried  versus 
moist  cultures— Penetrating  powers-  Effect  on  cultures  in  books— Quantities  of  chem- 
,icals 

Final  recommendations 


22-26 

27 


27 


Standard  Disinfectants 


‘PROVE  ALL  THINGS;  HOLD 
FAST  THAT  WHICH  IS  GOOD.’* 


“BE  SURE  OF  IT;  GIVE  ME 
THE  OCULAR  PROOF.” 


PRACTICAL  DISINFECTION. 


With  the  Results  of  Experimental  Work  Done  in  the  Laboratory 
of  the  Illinois  State  Board  of  Health,  in  Formalde- 
hyde Disinfection. 


General  Considerations. 

The  object  of  disinfection  in  the  sick  room  is  the  destruction  of 
infectious  material  attached  to  clothing,  carpets,  draperies,  furniture 
or  surfaces  of  the  room,  or  deposited  as  dust  upon  the  window  ledges, 
in  crevices,  cracks,  and  other  more  or  less  inaccessible  parts  of  the 
room.  If  the  room  has  been  properly  cleaned  and  ventilated  while 
still  occupied  by  the  sick  person,  and  especially  if  it  was  stripped  of 
carpets  and  unnecessary  furniture  at  the  onset  of  the  attack,  the 
difficulties  of  disinfection  will  be  greatly  reduced. 

The  ’work  of  disinfection  should  begin  wdth  the  beginning  of  the 
treatment  and  should  continue  during  the  whole  course  of  the  disease. 
All  articles  of  bed  clothing  and  of  body  clothing  should  be  disinfected 
as  soon  as  they  are  removed  from  the  bed  or  from  the  patient. 

The  liberal  use  of  liquid  disinfectants  composed  of  chloride  of 
lime,  carbolic  acid,  or  corrosive  sublimate  is  strongly  recommended  in 
the  sick  room,  but  there  should  be  no  attempt  to  disinfect  the  room 
by  any  vapors  or  gases  when  occupied  by  the  patient.  This  can  not 
be  accomplished.  Fresh  air,  combined  with  absolute  cleanliness,  is 
the  disinfectant  most  needed  in  the  sick  room. 

During  the  entire  illness  the  privy  should  be  thoroughly  dis- 
infected with  Standard 'Disinfectant  No.  1,  (see  page  28)  four  or  five 
gallons  of  which  should  be  thrown  into  the  vault  every  day.  Instead 
of  the  solution,  chloride  of  lime  in  powder  can  be  used.  All  wood- 
work in  the  vault  should  be  soaked  with  the  solution  or  covered  with 
powdered  lime.  Water  closets  and  sinks  should  be  disinfected  daily 
by  pouring  a quart  or  more  of  the  solution  of  chloride  of  lime  or  car- 
bolic acid  into  the  pipes.  The  pipes  should  be  freely  flushed  in 
order  to  avoid  injury. 

As  unsanitary  surroundings  and  uncleanliness  will  tend  to  retard 
the  recovery  of  the  patient,  every  effort  should  be  made  to  keep  the 
house,  cellar,  outhouses  and  yard  clean.  The  cellar  should  be  freed 
of  all  rubbish  and  decaying  matter  and  the  walls  whitewashed.  All 
rubbish  and  decaying  matter  should  be  burned.  Quicklime,  Standard 


6 


Disinfectant  No.  4,  (see  page  28)  can  be  well  used  to  whitewash  ex- 
posed surfaces  and  to  disinfect  sinks,  drains,  decaying  matter  too  wet 
to  be  burned,  pools  of  water,  etc.  Attempts  should  be  made  to  draw 
oflP  all  pools  of  water. 

In  the  disinfection  of  houses  which  have  been  occupied  by  those 
sufPering  from  contagious  or  dangerously  communicable  diseases, 
much  can  be  accomplished  by  the  liberal  use  of  liquid  disinfectants, 
by  thoroughly  washing  all  woodwork  and  exposed  surfaces,  and  by  the 
burning  of  mattresses  and  pillows,  by  the  removal  of  wall  paper  after 
saturati®n  with  disinfectants,  and  by  treating  carpets,  hangings  and 
other  fabrics  and  exposing  them  in  the  fresh  air  and  to  sunlight. 

The  ideal  disinfection  would  be  one  which  would  have  no  de- 
structive effect  upon  the  contents  of  the  room,  which  would  have  such 
penetrating  power  as  to  be  effective  upon  all  infectious  materials  how- 
ever inaccessible  they  might  be  and  which  could  be  applied  with  a 
minimum  of  labor.  Such  a disinfectant  has  never  been  found.  Gases 
are  decidedly  limited  as  to  penetrating  power  and  are  suited  only  for 
comparatively  superficial  disinfection.  Liquid  disinfectants  are  un- 
available for  many  uses.  It  is  consequently  essential  that  we  adopt 
both  the  aerial  and  the  liquid  disinfectants,  and  that  we  give  such  at- 
tention to  every  detail  that  no  article  and  no  part  of  the  room  escape 
being  subjected  to  the  suitable  disinfecting  agent  in  the  most  advan- 
tageous way. 


“Disinfectants,  or  germicides,  are  agents  which  bring  about  the  destruction 
of  bacteria  in  general  and,  more  particularly,  of  those  that  act  as  the  excit- 
ing causes  of  disease.  While  they  are  all  to  be  classed  as  antiseptics,  the 
latter,  as  a class,  are  by  no  means  necessarily  disinfectants,  since  many  of 
them  act  simply  to  delay  or  prevent  the  action  of  fermentative  agents,  with- 
out exerting  any  destructive  influence  upon  them.  Cold,  for  example,  is  a 
most  efficient  antiseptic;  but  while  it  may  inhibit  growth  and  activity  of 
micro-organisms,  it  does  not  necessarily  deprive  them  of  vitality. ’’-Harrington. 


AERIAL  DISINFECTION. 


The  most  effective  part  of  house  disinfection,  however,  is  acorn- 
plished  by  the  liberation  of  large  quantities  of  disinfecting  and  germ- 
icidal gases,  which  impregnate  the  air,  saturate  the  softer  fabrics, 
and  invade  the  most  inaccessible  and  remote  parts  of  the  room.  For 
this  aerial  disinfection  the  fumes  of  burning  sulphur  were  formerly 
accepted  by  all  health  officers  and  sanitarians,  but  in  more  recent 
years  formaldehyde  gas  has  been  used  and  exploited  and  has  acquired 
a high  degree  of  popularity. 

Whatever  the  agent  used  for  aerial  disinfection  with  fumes  or  gases 
the  following  certain  general  rules  are  essential  to  success,  and  may 
be  laid  down  for  adoption  both  by  those  who  adhere  to  sulphur  as 
the  disinfecting  agent  and  by  those  who  prefer  and  use  formaldehyde 
gas. 

Have  all  windows  and  doors  (except  doors  of  egress)  tightly 
closed.  Securely  paste  strips  of  paper  over  keyholes,  over  all  cracks,, 
above,  beneath  and  at  sides  of  windows  and  doors,  over  stove  holes,, 
and  all  openings  in  walls,  ceilings  and  floor.  If  the  opening  be  large,- 
paste  several  thicknesses  of  paper  over  it.  Carefully  stop  up  the^ 
fireplace,  if  there  be  one.  There  must  be  no  opening  through  which; 
gas  can  escape. 

(b)  All  articles  in  the  room  that  can  not  be  washed  should  be' 
spread  out  on  chairs  or  racks.  Clothing,  bed  covers,  etc.,  should  be* 
spread  on  lines  stretched  across  the  room.  Mattresses  should  be 
opened  and  set  on  edge.  Window  shades  and  curtains  should  be 
spread  out  at  full  length.  If  there  is  a trunk  or  chest  in  the  room, 
open  it,  but  let  nothing  stay  in  it.  Open  the  pillows  so  that  sulphur 
or  formaldehyde  fumes  can  reach  the  feathers.  Do  not  pile  articles, 
together. 

(c)  After  the  aerial  disinfection  is  completed  and  the  room 
opened,  take  out  all  articles  and  place  them  in  the  sunshine.  Carpets- 
should  be  well  beaten  and  exposed  to  the  sun. 

(d)  All  wood  surfaces  in  the  room  should  then  be  thoroughly 
washed  with  Standard  Disinfectant  No.  3.  (see  page  28.)  Wash  well 
all  out  of-the-way  places,  window  ledges,  mouldings,  etc.  Floors  par- 
ticularly should  receive  careful  attention  and  the  solution  should  wet 
the  dust  and  dirt  in  the  cracks.  If  the  walls  are  papered,  soak  the 
paper  with  the  solution  and  have  it  removed. 

(e)  After  washing,  ventilate  the  rooms,  if  possible  for  several 
hours,  then  scrub  all  woodwork  with  soap  and  hot  water. 

(/)  It  is  safer  to  burn  mattresses  and  pillows. 


8 


{g)  It  is  likewise  safer  to  burn  all  books,  toys  and  articles  of 
little  value  which  have  been  handled  by  the  patient.  Burn  what  you 
cannot  boil  or  thoroughly  wash.  Books  which  have  not  been  in  the 
room  with  the  patient  may  he  saved.  Lay  them  on  edge  of  a table 
table  with  leaves  open,  in  room  while  sulphur  fumes  or  formaldehyde 
gases  are  being  generated. 

It  must  be  borne  in  mind  that  thoroughness  of  application  is  most 
essential,  whatever  method  of  disinfection  may  be  adopted.  Careless- 
ness in  the  slightest  detail  may  be  productive  of  the  gravest  danger 
to  those  whose  confidence  has  been  inspired  by  the  assurances  of 
safety. 

Although  the  patient  suffering  from  contagious  disease  may  have 
been  confined  to  one  room,  it  must  not  be  forgotten  that  the  avenues 
for  the  transmission  of  infective  material  to  other  parts  of  the  house 
are  never  entirely  shut  off  so  long  as  there  is  any  communication 
between  the  sickroom  and  other  rooms.  Even  the  sheet,  saturated 
with  liquid  disinfectants,  which  experience  has  taught  us  to  hang 
over  the  open  door  of  the  sickroom,  may  not  serve  as  a barrier  to  all 
infectious  material,  especially  if  the  nurse,  the  physician  and  mem- 
bers of  the  family  pass  frequently  from  the  sickroom  to  other  parts 
of  the  house.  Hence,  after  cases  of  particularly  contagious  nature, 
not  only  the  sickroom  but  all  rooms  contiguous  to  it  should  be 
thoroughly  disinfected. 


Notes  Concerning  Insecticides. 

A few  words  here  regarding  the  agents  which  can  he  depended  upon  to 
destroy  vermin  will  certainly  not  be  out  of  place. 

Some  authorities  have  recommended  formaldehyde  as  an  insecticide. 
Those  who  have  personally  experimented  with  this  agent  know  that  it  can 
not  be  depended  upon  to  even  kill  mosquitoes  in  a room.  Formaldehyde  gas 
is  but  a feeble  insecticide  at  best.  It  is  never  efficacious  except  when  the  gas 
is  generated  quickly  and  in  large  volume.  Even  then  the  results  may  be  dis- 
appointing. 

Formaldehyde  has  ordinarily  but  little  penetrating  power.  Usually  the 
gas  will  not  reach  the  folds  of  bedding  and  clothing,  and  out-of-the-way 
places  in  which  vermin  are  prone  to  hide. 

As  to  sulphur,  which  is  not  only  a reliable  disinfectant,  but  also  a power- 
ful and  reliable  insecticide,  the  following  remarks  of  Surgeon  M.  J . Rosenau, 
Director  Hygienic  Laboratory,  U.  S.  Public  Health  Service,  will  be  inter- 
esting: 

“Sulphur  dioxide  is  unexcelled  as  an  insecticide.  Very  dilute  atmos- 
pheres of  the  gas  will  quickly  kill  mosquitoes.  It  is  quite  as  efficacious  for 
this  purpose  when  dry  as  when  moist,  whereas  the  dry  gas  has  practically  no 
power  against  bacteria.  Contrary  to  formaldehyde  it  has  surprising  powers 
of  penetration  through  clothing  and  fabrics,  killing  the  mosquitoes,  even 
when  hidden  under  four  layers  of  toweling,  in  one  hour’s  time — and  with 
very  dilute  proportions. 

“This  substance,  which  has  so  long  been  disparaged  as  a disinfectant  be- 
cause it  fails  to  kill  spores,  must  now  be  considered  as  holding  the  first  rank 
in  disinfection  against  yellow  fever,  malaria,  filariasis,  and  other  insect-borne 
diseases.” 


9 


SULPHUR  DISINFECTION. 


Disinfection  by  the  burning  of  sulphur  has  been  successfully 
practiced  for  many  years.  As  stated  by  Surgeon  General  Sternberg, 
United  States  Army,  “ the  experience  of  sanitarians  is  in  favor  of  its 
use  in  yellow  fever,  small-pox,  scarlet  fever,  diphtheria  and  other 
diseases  in  which  there  is  reason  to  believe  that  the  infectious  ma- 
terial does  not  contain  spores.”  This  method  of  disinfection  has  also 
been  endorsed  recently  by  the  United  States  Marine  Hospital  Service, 
after  numerous  experiments,  during  which  the  efficacy  of  sulphur  dis- 
infection, in  the  presence  of  moisture,  was  conclusively  proven. 

The  results  obtained  by  the  Illinois  State  Board  of  Health,  in  the 
several  experiments  made,  have  been  directly  in  line  with  those  of 
other  investigators.  The  burning  of  sulphur  in  the  presence  of  mois- 
ture has  been  found  an  effectual  method  of  gaseous  disinfection,  and 
one  upon  which  entire  dependence  can  be  placed  at  all  times  in  disin- 
fection after  diseases  due  to  micro-organisms  not  containing  spores. 

After  the  preparation  of  the  room,  as  described  on  page  7,  reliable 
and  cheap  disinfection  may  be  secured  by  the  following  method  of 
the  use  of  sulphur. 

(1)  Use  three  pounds  of  powdered  sulphur  for  every  1,000  cubic 
feet  in  the  room.  A room  ten  feet  long,  ten  feet  wide  and  ten  feet 
high  has  1,000  cubic  feet.  For  a large  closet  use  two  pounds  of  sul- 
phur. 

(2)  Burn  the  sulphur  in  an  iron  pot  or  deep  pan.  Let  the  pot 
or  pan  stand  in  a larger  vessel  containing  water,  which  vessel  should 
be  placed  on  a table,  not  on  the  floor.  For  example,  take  a common 
wash  tub,  lay  in  it  three  or  four  bricks,  pour  in  boiling  water  to  the 
level  of  tops  of  bricks,  put  the  pot  or  pan  containing  the  required 
amount  of  sulphur  on  the  bricks,  place  the  wash  tub  and  contents  on 
a table.  The  disinfecting  “apparatus”  is  then  in  working  order. 

(8)  Moisten  the  sulphur  with  alcohol  and  ignite.  When  the 
sulphur  begins  to  burn,  leave  the  room,  close  the  door  of  egress,  and 
carefully  paste  strips  of  paper  over  the  keyhole  and  all  openings 
above,  beneath  and  at  sides  of  door.  Keep  the  room  closed  for  ten 
hours  at  least,  twenty-four  if  possible. 

Sulphur  candles  may  be  used  instead  of  crude  sulphur,  but  care 
must  be  taken  to  use  sufficient  candles.  The  average  candle  on  the 
market  contains  one  pound  of  sulphur.  Three  of  these  will  be  re- 
quired in  the  disinfection  of  a small  room  10x10x10.  Do  not  use  a 
less  number,  no  matter  what  directions  may  accompany  the  candle. 
The  water- jacketed  candle  is  preferable.  Partly  fill  tin  around  candle 
with  water  and  place  candles  in  a pan  on  the  table,  not  on  the  floor. 


10 


Let  at  least  one-half  pint  of  water  be  evaporated  with  each  candle. 
Evaporate  more  if  practicable.  In  the  absence  of  moistnre,  the 
fumes  of  sulphur  have  no  disinfecting  power. 

. There  is,  however,  one  serious  objection  to  the  use  of  sulphur, 
and  this  must  be  fully  understood.  The  fumes  of  sulphur  (sulphur- 
ous acid)  have  a destructive  action  on  the  fabrics  of  wool,  silk,  cotton 
and  linen,  on  tapestries  and  draperies,  and  exercise  an  injurious  influ- 
ence on  brass,  copper,  steel  and  gilt  work.  Colored  fabrics  are  fre- 
quently changed  in  appearance  and  the  strength  impaired.  Fabrics, 
however,  can  be  effectually  disinfected  by  hanging  them  on  a line  ex- 
posed to  the  sun  and  wind  for  several  days.  Curtains  and  all  articles 
of  cotton  or  linen,  boiling  or  soaking  them  in  Standard  Disinfectant 
No.  B,  for  several  hours,  and  portable  articles  of  brass,  copper,  steel 
and  gilt  work  by  washing  with  a strong  solution  of  carbolic  acid 
(Standard  Disinfectant  No.  1).  Colored  fabrics  which  have  been  in 
a room  during  disinfection  should  be  immediately  exposed  to  the  sun 
and  wind.  Uncolored  fabrics  which  will  not  be  injured  by  moisture 
should  be  at  once  soaked  in  water.  This  action  will  prevent  further 
injurious  action  of  the  sulphuric  acid. 

Sulphur  will  be  found  a thoroughly  reliable  gaseous  disinfectant 
of  considerable  penetrating  power,  if  it  is  intelligently  employed.  To 
obtain  satisfactory  results,  the  following  essentials  of  successful  dis- 
infection, established  by  repeated  experiments,  must  be  observed: 
(a)  The  infected  room,  or  rooms,  must  be  thoroughly  closed,  every 
crack  and  crevice  sealed.  (6)  Sufficient  sulphur  must  be  used, 
(c)  There  must  be  moisture  in  the  room,  {d)  The  time  of  exposure 
must  be  sufficient,  ten  hours  the  minimum. 

In  the  disinfection  of  stores,  halls,  school  houses  and  apartments 
or  dwellings,  in  which  there  are  no  articles  to  be  injuriously  affected 
by  the  gas,  sulphur  is  an  ideal  disinfectant.  Its  mode  of  application 
is  simple  (the  simpler  the  mode  of  application  the  better),  it  is  cheap, 
the  material  is  accessible  everywhere,  and,  finally,  the  most  important 
of  all,  the  action  will  be  invariably  found  effective  when  the  sulphur 
is  properly  used. 


“Cleanliness  is  an  important  adjunct  to  the  work  of  disinfection. 
*•»•***** 

“Cleanliness  accomplishes  another  important  purpose  as  far  as  infection 
is  concerned;  it  removes  the  organic  matter  on  which  and  in  which  the  bac- 
teria find  favorable  conditions  for  prolonging  life  and  virulence.” — Rosenau^ 


11 


FOKMALDEHYDE  DISINFECTION,^ 


On  account  of  the  destructive  properties  of  sulphur,  efforts  have 
been  made  to  find  a satisfactory  substitute  for  this  agent,  one  of 
equal  germicidal  power,  which  will  not  damage  the  contents  of  the 
room.  If  dependence  could  be  placed  on  the  published  results  of  in- 
numerable experiments  made  with  formaldehyde,  there  would  be  no 
necessity  for  further  search  for  the  much  desired  substitute.  For- 
maldehyde has  been  lauded  as  the  most  powerful  sterilizer  and  germi- 
cide known;  as  a gaseous  disinfectant  far  superior  in  efficiency  to 
sulphur — one  seemingly  without  limitations,  effective  at  all  times. 
The  results  obtained  by  careful  observers  in  experiments  made,  not  in 
laboratories,  but  in  dwelling  houses,  shops  and  railroad  cars,  in  which 
disease  is  often  found,  do  not  substantiate  the  extravagant  claims 
made  for  formaldehyde. 

Formaldehyde  (otherwise  known  as  methyl  aldehyde,  formicalde- 
hyde  and  “ formalin  ”)  exists  in  several  forms,  but  is  principally 
known  as  a gas.  Its  germicidal  properties  were  not  recognized  until 
1886.  and  were  not  put  to  use  until  1890.  The  formaldedyde  gas  is 
the  vapor  of  wood  alcohol  which  has  undergone  a chemical  change. 
The  gas  is  produced  by  passing  the  vapor  of  wood  alcohol  over  plati- 
num or  platinized  carbon  in  an  incandescent  state.  Many  portable 
apparatus  for  the  production  of  formaldehyde  gas  directly  from  wood 
alcohol  have  been  devised  during  the  past  ten  years.  The  writer 
made  a series  of  experiments  in  1896-7,  while  connected  with  the  Chi- 
cago Health  Department,  with  the  lamps  then  on  the  market.  The 
tests  were  conducted  in  the  most  painstaking  and  careful  manner,  but 
in  every  instance  the  results  were  unsatisfactory.  It  was  found  that 
the  lamps  did  not  give  off  sufficient  formaldehyde;  that  the  alcohol 
was  generated  too  slowly,  and  that  large  quantities  of  alcohol  passed 
through  the  lamp  unchanged.  But  few  bacteria  were  killed  by  the 
gas  evolved.  There  was  consequently  no  disinfection.  Not  one  of 
these  lamps  so  highly  endorsed  in  1896  as  ideal  apparatus  for  the 
production  of  formaldehyde  gas  is  now  offered  for  sale.  Experiments 
were  made  at  the  same  time  under  the  best  possible  conditions  with 
the  generator  in  which  the  fluid  formaldehyde  was  boiled  and  vapor- 
ized. Disinfection  failed  in  nearly  all  these  experiments. 

In  1898  the  State  Board  of  Health  commenced  experiments  for 
the  purpose  of  confirming  or  disproving  the  many  claims  made  for 
formaldehyde  by  sanitary  authorities  at  home  and  abroad,  and  inci- 
dentally for  the  purpose  of  finding  a practical  method  of  disinfection 
with  this  agent.  These  experiments  were  made  under  the  direction 


♦ See  page  15  for  method  recommended. 


12 


of  Professor  T.  J.  Burrill,  of  the  University  of  Illinois,  and  were  con- 
tinued at  intervals  until  1902.  The  results  of  the  experiments  are  as 
indicated  below. 

The  aqueous  solution  of  formaldehyde  gas,  known  as  formalde- 
hyde and  ‘Tormalin,”  is  a 40  per  cent  solution  of  the  gas  formaldehyde 
in  water.  It  is  claimed  that  many  of  the  commercial  preparations  do 
not  contain  40  per  cent  of  formaldehyde.  Several  processes  have  been 
devised  for  the  liberation  of  formaldehyde  gas  from  its  watery  solu- 
tion. The  solution  when  exposed  to  the  air  gives  off  a considerable 
quantity  of  the  gas,  especially  when  sprayed  on  large  surfaces.  If 
the  solution  be  sprayed  on  blankets  or  sheets  or  articles  of  clothing 
hung  in  the  room  or  on  the  walls,  the  liberation  of  the  gas  will  be  so 
rapid  as  to  compel  the  operator  to  leave  the  room.  These  facts  have 
given  rise  to  the  belief  that  exposure  of  the  gas  in  this  manner  will 
be  sufficient  to  cause  disinfection.  The  results,  however,  do  not  con- 
firm this.  There  is  much  uncertainty  as  to  the  amount  of  gas  which 
is  evolved,  and  the  behavior  of  the  gas  is  at  times  capricious. 

It  has  been  determined  by  the  United  States  Public  Health  Service 
after  a series  of  extended  experiments  conducted  by  Past  Assistant 
Surgeon  M.  J.  Rosenau,  that  formaldehyde  sprinkled  on  blankets  and 
sheets  has  practically  no  disinfecting  power  in  a closed  box,  excepting 
on  the  spot  where  the  solution  falls;  this  after  a twenty-four  exposure. 

The  amount  of  gas  given  off  from  the  aqueous  solution  of  formal- 
dehyde at  ordinary  temperatures  is  exceedingly  small.  After  the 
solution  has  been  applied  to  exposed  surfaces,  the  liquid  becomes 
concentrated,  and  as  found  years  ago  by  Surgeon  J.  J.  Kinyoun  of 
the  United  States  Public  Health  Service,  the  greater  proportion  of  the 
formaldehyde  gas  is  converted'  into  a yellowish  white  amorphous 
substance  known  as  trioxy-methelene.  In  this  state  it  gives  off  but  a 
slight  amount  of  formaldehyde. 

The  State  Board  of  Health  conducted  a number  of  exper- 
iments during  the  years  1899-1902  to  test  the  efficiency  of  the  so- 
called  “sheet  method”  of  disinfection,  which  consists  of  suspending 
sheets  in  the  infected  room,  and  spraying  them  with  a solution  of 
formaldehyde,  using  about  six  ounces  of  the  forty  per  cent,  solution 
to  each  thousand  cubic  feet  of  air  space.  The  results  with  this  method 
have  not  be.en  satisfactory.  At  times  under  favorable  conditions  the 
method  proved  effective,  while  again  under  almost  identical  condi- 
tions, it  was  found  worthless,  even  when  the  amounts  of  formaldehyde 
on  the  areas  of  sheet  surface  were  increased.  At  temperatures  below 
60*’  F.  the  results  were  invariably  unsatisfactory. 

To  ensure  good  results  with  this  method  it  is  absolutely  neces- 
sary that  the  sheets  be  sprayed  evenly  in  small  drops  over  the  entire 
surface,  care  being  taken  not  to  go  over  the  same  surface  twice.  Even 
the  most  enthusiastic  advocates  of  the  “sheet  method”  admit  that  the 
results  will  be  unfavorable  unless  this  precaution  be  observed.  For- 
maldehvde  is  exceedingly  irritating  to  the  respiratory  passages  and  to 
the  eyes,  so  that  it  becomes  a test  of  human  endurance  to  remain  in  a 
room  for  the  time  necessary  to  properly  spread  sufficient  solution  to 


18 


disinfect  a very  small  space,  while  in  a room  of  ordinary  dimensions, 
which  would  require  a number  of  sheets,  the  proper  spreading  of  the 
solution  by  one  man  becomes  a matter  of  absolute  impossibility.* 

The  ordinary  disinfector  working  under  conditions  so  decidedly 
unpleasant  will,  in  the  majority  of  instances,  slight  his  work,  so  that 
even  if  the  sheet  method  were  much  more  efficient  than  it  is,  the  re- 
sults of  its  practical  application  would  seldom  be  satisfactory. 

These  conclusions  have  been  reached  by  diflPerent  State  Boards 
of  Health  throughout  the  country,  which  have  made  personal  inves- 
tigations into  the  efficacy  of  this  mode  of  disinfection. 

Rosenau.  of  the  United  States  Public  Health  Service,  says,  that 
the  “sheet  method”  has  distinct  limitations  and  unless  all  necessary 
conditions  are  carefully  observed,  is  very  untrustworthy.  The  gas  is 
given  off  very  slowly  and  in  very  uncertain  quantity,  diffuses  poorly 
in  dead  spaces  and  is  entirely  inapplicable  to  large  enclosures.  Even 
when  conducted  with  the  utmost  care,  the  method  is  limited  to  rooms 
not  exceeding  2.0CO  cubic  feet. 

In  view  of  the  fact  that  it  is  practically  impossible  for  a disinfector 
to  properly  spray  the  sheets,  over  a sufficient  area  to  have  effect  in 
rooms  of  more  than  small  dimensions;  in  view  of  the  fact  that  there 
will  be  no  disinfection  unless  the  sheets  be  properly  sprayed;  in  view 
of  the  fact  that  the  method  is  utterly  worthless  at  even  reasonably 
low  temperatures,  and  further  in  view  of  the  unreliability  of  the 
method,  indicated  in  the  numerous  failures  to  kill  bacteria,  even  of 
feeble  resisting  powers,  when  technique  seemed  perfect  and  condi- 
tions favorable,  the  Illinois  State  Board  of  Health  can  not  recommend 
its  use  to  physicians  or  health  authorities.  “An  effective  method  of 
disinfection  must  have  no  exceptions;  it  must  invariably  kill.” 

The  most  common  method  of  obtaining  formaldehyde  gas  from  the 
watery  solution  at  the  present  time  is  by  means  of  apparatus  designed 
to  regenerate  the  gas  by  boiling  the  solution  under  pressure.  Many 
generators  operating  on  this  principle  are  to  be  found  on  the  market. 
Several  of  these  are  complicated  machines  requiring  skill  to  properly 
operate.  As  some  of  the  generators  require  constant  attention,  it  has 
been  found  necessary  to  place  them  outside  of  the  apartment  being 
disinfected  and  to  pass  the  gas  into  the  room  by  means  of  a tube  run 
through  a keyhole.  The  diffusion  of  the  gas  produced  in  this  way  is 
slow,  particularly  in  large  areas,  tending  to  its  concentration  at  a few 
points  and  to  the  formation  of  paraform.  This  method  of  disinfection 
cannot  be  recommended.  To  insure  a perfect  disinfection  with  for- 
maldehyde it  is  necessary  that  the  gas  be  liberated  quickly  and  in 
large  volume. 

Formaldehyde  “candles”  composed  of  paraform  are  now  offered  to 
health  authorities  as  a means  of  disinfection.  No  dependence  what- 
ever should  be  placed  on  these  candles. 

* Laboratory  Investigations.  * * * Spraying-  a sheet  with  formal" 
dehyde  while  the  operator  is  standing  in  front  of  the  sheet  is  a procedure 
claimed  to  be  possible  only  by  those  who  have  never  tried  it,  and  describe  it 
from  imagination.  * After  ten  ounces  had  been  sprayed  further  operation 
was  rendered  impossible  by  the  unbearable,  irritating  vapor  of  the  formalde- 
hyde; ^ ^ Disinfection  not  obtained  in  experiments  conducted; — Bulletin 

of  the  Pathological  and  Bacteriological  Laboratory  of  the  Delaware  State  Board  of 
Health. 


14 


The  evaporation  of  the  solution  of  formaldehyde  by  the  means  of 
heat  in  an  ordinary  kettle  is  one  of  the  simplest  methods  of  disinfec- 
tion with  formaldehyde,  and  the  results  have  proven  effective.  This 
method  was  endorsed  by  the  writer  in  1896.  This  is  termed  the 
Breslau  method.  Many  health  authorities  have  testified  to  its  efficiency 
during  the  past  eight  years.  To  quote  from  the  monthly  report  of 
the  Chicago  Health  Department  of  January,  1898,  in  which  this  pro- 
cess is  described  at  length  and  heartily  endorsed:  “A  six  hours’ 

exposure  under  these  conditions  has  given  better  results  in  the  steril- 
ization of  cultures  than  has  been  obtained  by  any  other  method,  and 
the  other  requirements — of  simplicity  and  portability  of  apparatus, 
rapid  evolution  of  the  disinfecting  agent  and  brief  duration  of  expos- 
ure, together  with  reasonable  cost  of  disinfection — are  very  nearly 
met.” 

A very  simple  apparatus  for  disinfection  by  this  method  was  de- 
vised by  the  Health  Department  of  St.  Louis  in  1898.  This  consists 
of  a copper  kettle  for  the  disinfectant,  a tripod,  and  a copper  vessel 
containing  mineral  wood  for  the  alcohol.  When  the  apparatus  is 
placed  in  order  the  kettle  is  partly  filled  with  hot  water  and  the  alco- 
hol in  the  vessel  beneath  is  ignited.  As  soon  as  the  water  boils  there 
is  poured  into  the  kettle  a quantity  of  the  40  per  cent  solution  of  for- 
maldehyde, forty  ounces  being  sufficient  for  the  disinfection  of  2,000 
cubic  feet  of  air  space.  In  order  to  produce  sufficient  moisture,  there 
is  used  in  addition  a similar  apparatus  in  which  water  alone  is  boiled. 
The  State  Board  of  Health  conducted  many  experiments  with  this 
apparatus,  and  the  results  have  been  generally  satisfactory,  and  it  is 
evident  that  the  apparatus,  when  properly  used,  can,  under  favorable 
conditions,  be  relied  upon  to  produce  a proper  amount  of  formalde- 
hyde gas  of  the  highest  efficiency.  After  repeated  tests  made  at  in- 
tervals from  1899  to  1901,  the  Board  feels  justified  in  endorsing  this 
method  of  disinfection  with  formaldehyde,  with  a proper  apparatus. 

To  obtain  proper  results  with  this  or  any  other  apparatus  it  is  ab- 
solutely necessary  that  the  best  formaldehyde  or  formalin  be  obtained 
Much  of  the  formaldehyde  sold  in  the  United  States  under  different 
names  cannot  be  relied  upon.  To  be  effective  formaldehyde  must 
contain  not  less  than  38  per  cent  of  strength.  There  is  also  much 
difference  in  the  quality  of  wood  alcohol  found  on  the  market.  Alco- 
hol 95  per  cent  proof  must  be  used  in  this  apparatus. 

The  best  imported  formaldehyde  (formalin)  was  used  in  all  the 
experiments  conducted  by  the  Illinois  State  Board  of  Health. 

In  disinfection  with  formaldehyde  the  same  precautions  relative  to 
the  sealing  of  the  room  should  be  taken  as  in  disinfection  with  sulphur. 
It  must  be  borne  in  mind  also  that  the  gas  of  formaldehyde,  unlike 
like  that  of  sulphur,  has  but  feeble  penetrating  power.  There  is  no 
doubt,  however,  that  the  gas  of  formaldehyde  will  penetrate  wherever 
infection  has  been  carried  by  the  surrounding  atmosphere. 


15 


THE  FOKMALDEHYDE  AND  POTASSIUM  PERMANOA- 
NATE  METHOD  OF  GENERATING 
FORMALDEHYDE  GAS. 


The  Method  Recommended.  * 

While  the  results  obtained  with  some  of  the  methods  of  formalde- 
hyde disinfection  formerly  suggested  have  been  generally  satisfactory, 
failures  were  at  times  experienced  when  the  conditions  were  ap- 
parently ideal,  while  under  unfavorable  conditions  of  temperature  and 
humidity,  ineffective  disinfection  was  of  frequent  occurrence.  For 
this  reason,  while  placing  before  the  physicians  and  health  officers  of 
the  state  the  best  methods  of  formaldehyde  disinfection,  the  State 
Board  of  Health  has  continued  to  advocate  sulphur  for  aerial  disin- 
fection as  the  only  agency  which  had  demonstrated  beyond  question 
its  efficiency  and  reliability  at  all  times. 

Aside  from  the  uncertainty  of  results  of  the  methods  of  formalde- 
hyde disinfection  offered  for  use,  the  apparatus  has  often  been  com- 
plicated in  operation,  unnecessarily  expensive  and  dangerous  as  to 
destruction  of  property  by  fire. 

An  exceedingly  simple  method  of  generating  the  gas  by  pouring 
formaldehyde  solution  over  the  crystals  of  potassium  permanganate 
in  an  open  vessel,  has  been  more  recently  suggested  and  gave  promise 
of  overcoming  the  objections  which  have  stood  in  the  way  of  the  more 
general  adoption  of  formaldehyde  as  a disinfecting  agent.  This 
method  primarily  offered  the  advantages  of  absolute  simplicity  in 
operation,  requiring  no  special  apparatus  and  no  fire.  In  addition  to 
this,  exhaustive  experimental  work  has  demonstrated  that,  in  practical 
disinfection,  the  method  is  unusually  efficient,  the  effectiveness  seem- 
ing to  depend  less  upon  the  conditions  of  humidity  and  temperature 
than  that  of  any  other  method. 

The  only  apparatus  required  is  a large  open  vessel,  protected  by 
some  non-conductive  material  to  preserve  the  heat  within.  An  ordi- 
nary milk  pail,  set  into  a pulp  or  wooden  bucket  will  answer  every 
purpose,  although  a special  container,  devised  for  physicians  and 
health  officers,  will  be  found  of  considerable  advantage.  This  con- 
tainer or  generator  consists  of  a simply  constructed  tin  can  with 
broad  flaring  top.  Its  full  height  is  15J  inches,  the  height  of  the 
flaring  or  funnel-shaped  top  being  about  8 inches.  The  lower  or 
round  section  is  10  inches  in  diameter,  while  the  funnel  top  is  17J 
inches  in  diameter  at  the  top.  This  container  is  made  of  a good 
quality  of  tin,  is  supplied  with  a double  bottom  with  a layer  of  as- 
bestos between  the  layers  of  tin,  and  is  entirely  covered  on  the  out- 


16 


DISINFECTING  APPARATUS. 

(Designed  by  the  Maine  State  Board  of  Health.) 

Heig’ht,  15)^  inches;  heig-ht  of  lower  portion,  8 inches;  diameter  at  top, 
173^  inches;  diameter  at  base,  10  inches.  Made  of  bright  tin  and  covered  with 
asbestos  paper. 


17 


side  with  asbestos  paper.  The  asbestos  paper  and  double  bottom 
serve  to  effectively  retain  the  heat  which  is  generated  by  the  vigorous 
chemical  reaction  occurring  within  the  generator,  and  which  is  es- 
sential to  the  complete  production  and  liberation  of  the  gas.  The 
special  retainer  can  be  made  by  any  tinner  of  ordinary  intelligence, 
and  costs  but  a few  dollars. 

This  method  of  aerial  disinfection  was  first  suggested  in  1902-3, 
but  it  was  given  no  publicity  until  1904,  when  it  was  described  by 
Dr.  G.  A.  Johnson,  of  Sioux  City,  Iowa,  in  a paper  read  before  the 
Sioux  Valley  Medical  Association.  Even  then  it  attracted  very  little 
attention  and  was  not  subjected  to  systematic  tests  until  late  in  1904. 
when  numerous  experiments  were  made  by  the  Maine  State  Board  of 
Health. 

The  test-bacteria  used  in  the  experiments  of  the  Maine  board  were 
diphtheria,  typhoid,  staphylococcus  albus  and  aureus,  coli  communis, 
pyocyaneus,  tetragenus,  streptococci,  anthrax,  subtilis,  and  mixed 
cultures  mostly  from  swabs  from  the  throats  of  patients  thought  to 
have  diphtheria.  The  time  of  exposure  was  at  first  16  hours,  but 
this  was  gradually  reduced  to  3 hours  with  no  lessening  efficiency. 

Of  the  1,529  test  objects  exposed  in  279  experiments,  only  twenty- 
seven  showed  a growth  after  incubation  for  at  least  48  hours.  Of 
these  twenty-seven  unsuccessful  results,  twenty-one  were  with  the 
exceedingly  resistant  hay  bacillus  (B.  subtilis).  None  of  the  bacilli 
of  diphtheria,  typhoid  fever  or  other  ordinary  pathogenic  germs  sur- 
vived the  exposure  to  formaldehyde. 

While  placing  great  dependence  on  the  results  obtained  by  the 
Maine  State  Board  of  Health,  the  Illinois  State  Board  of  Health 
decided  to  pursue  the  policy  adhered  to  since  1898,  to  make  a sys- 
tematic test  of  all  methods  of  disinfection  recommended  before  en- 
dorsing or  condemning  the  methods. 

During  the  summer  and  autumn  of  1905  exhaustive  experimental 
investigations  were  carried  on  with  this  method  of  disinfection  in  the 
laboratories  of  the  State  Board  of  Health  at  Springfield.  An  ordin- 
ary office  room,  containing  1,080  cubic  feet  of  air  space,  was  secured, 
situated  conveniently  to  the  laboratory.  The  door  was  carefully 
sealed  with  strips  of  gummed  paper  and  access  to  the  room  was 
gained  through  an  outer  window.  This  window,  was  not  protected  by 
paper  strips,  but  set  closely  in  its  frame. 

Twenty-four  (24)  hour  bouillon  cultures  of  various  forms  of  bacteria 
were  prepared.  Strips  of  milk  paper  in.  x 2 in.  ) were  saturated 
with  these  cultures.  The  slips  were  saturated  in  pairs,  one  slip  being 
exposed  to  the  fumes  of  the  gas  in  the  room,  the  other  placed  in  a 
sterile  envelope,  sealed,  labeled  and  kept  in  the  laboratory  to  be  used 
as  a control.  After  the  exposure  of  the  first  slip  to  the  fumes  of  the 
gas  generated  by  pouring  the  40%  formaldehyde  solution  over  the 
permanganate  of  potassium  in  the  usual  manner,  it  was  returned  to 
the  laboratory,  both  slips  placed  each  in  a tube  of  sterile  bouillon, 
incubated  at  37°  C.  for  48  hours,  and  later  examined  and  compared. 

On  account  of  the  variable  results  obtained  by  other  methods  of 
formaldehyde  disinfection,  depending  largely  upon  the  temperature 


18 


and  atmospheric  conditions,  days  were  selected  for  experimental 
work  which  varied  greatly  in  temperature,  humidity,  cloudiness  and 
other  climatic  conditions,  and  these  conditions  were  made  a part  of 
the  laboratory  records. 

Specimens  were  exposed  for  a period  of  6 hours  and,  between  ex- 
periments, the  room  was  left  open  that  it  might  be  entirely  freed  of 
any  traces  of  formaldehyde  gas. 

The  results  of  experiments  of  the  Illinois  State  Board  of  Health 
are  shown  in  the  tables  on  pages  19  and  20. 

It  will  be  noted  in  the  tables  of  laboratory  tests  that  the  bacterial 
growth  was  entirely  destroyed  when  one  quart  (32  oz.)  of  formalde- 
hyde was  used  to  the  1,000  cubic  feet  of  air  space,  and  that  equally 
satisfactory  results  were  obtained  with  one  pint  (16  oz.)  of  formalde- 
hyde. It  may  consequently  be  stated  that,  under  ordinary  conditions 
of  house  disinfection,  the  room  being  well  sealed,  a pint  (16  oz.)  of 
formaldehyde  solution  with  6f  oz.  of  potassium  permanganate  will  be 
ample  for  1,000  cubic  feet  of  air  space.  With  these  amounts  bacterial 
cultures,  enclosed  in  from  one  to  four  layers  of  4^  oz.  flannel,  were 
destroyed,  these  cultures  including  the  bacillus  subtilis  (hay  bacillus) 
known  to  be  especially  resistant  to  formaldehyde  gas.  It  is  not  yet 
determined  how  small  quantities  of  formaldehyde  and  permanganate 
of  potassium  will  produce  satisfactory  results,  but  it  is  the  part  of 
wisdom  not  to  economize  in  materials  if  there  is  the  slightest  danger 
of  reducing  the  germicidal  power.  Even  with  the  largest  quantities 
named,  a quart  of  formaldehyde  to  13^  oz.  of  potassium  permangan- 
ate, the  cost  is  small. 

It  might  be  noted  in  this  connection  that  the  Maine  State  Board 
of  Health  adopted  in  its  experiments  the  proportion  of  6^  oz.  of 
potassium  permanganate  to  32  oz.  of  formaldehyde  for  each  1,000 
cubic  feet  of  air  space,  and  in  a recent  circular  still  recommends  these 
amounts.  However,  as  stated  above,  it  has  been  the  experience  of 
the  Illinois  State  Board  of  Health  that  under  proper  conditions,  (at 
temperatures  above  60°  F.)  one  pint  (16  oz.)  of  formaldehyde  (the 
40^0  solution  ) with  6|  oz.  of  potassium  permanganate  will  be  sufficient 
for  the  disinfection  of  1,000  cubic  feet  of  room  space. 

The  results  obtained  with  this  method,  in  experiments  conducted 
by  the  Illinois  State  Board  of  Health,  under  varying  atmospheric 
conditions  and  with  a rather  wide  range  of  temperature,  indicate 
that  there  has  been  Anally  found  a method  of  formaldehyde  disin- 
fection which  will  prove  effective  under  reasonable  conditions,  at 
temperatures  ordinarily  found  in  the  living  or  sleeping  rooms, 
while  the  simplicity,  the  small  expense  of  apparatus  (in  fact, 
its  successful  operation  without  apparatus  of  any  kind,  if 
necessary)  and  the  moderate  cost  of  operation,  serve  to  commend 
it.  In  the  work  of  the  State  Board  of  Health  the  best  quality 
of  imported  formaldehyde  (formalin)  was  employed,  and  Merck’s 
potassium  permanganate,  but  even  with  the  highest  grade  of  ma- 
terials the  cost  is  small. 

It  must  be  borne  in  mind  that  the  quantities  of  potassium  perman- 
ganate and  formaldehyde  set  forth  above,  should  be  used  only 


Forinaldehijde — Potassium  Permanganate  Method. 


19 


Ti 

w 

OS 


P- 

3 


W 

X 


Bacillus  Subtilis. .. 

bi) 

<u 

be 

0) 

■be 

0) 

bi) 

V 

bi) 

0) 

be 

4; 

be 

4J 

bi) 

4; 

bi) 

4; 

be 

01 

z 

Z 

Z 

z 

z 

Z 

Z 

Z 

Z 

Z 

Staphy.  Pyogenes 

be 

<u 

bi) 

4; 

be 

V 

be 

(U 

be 

0) 

be 

0) 

be 

V 

bi) 

lU 

bi) 

0) 

le 

0) 

bi) 

4; 

hei 

01 

be 

0) 

be 

4) 

Z 

Z 

Z 

Z 

z 

Z 

z 

Z 

Z 

z 

Z 

Z 

Z 

Z 

Staphy.  Pyogenes 

be 

V 

bi) 

V 

bi) 

<u 

bi) 

o> 

be 

O) 

be 

01 

be 

<u 

bi) 

0) 

bi) 

01 

be 

0) 

bi) 

4) 

be 

V 

be 

01 

Z 

be 

4i 

Z 

Z 

Z 

z 

Z 

Z 

Z 

Z 

z 

Z 

z 

Z 

Z 

Staphy.  Pyogenes 

be 

D 

be 

<u 

bi) 

a; 

bi) 

0) 

bi) 

<u 

bi) 

01 

be 

01 

bi) 

0) 

bi) 

0) 

bi) 

4) 

bi) 

0) 

bi) 

OI 

bi) 

01 

be 

4; 

Z 

Z 

Z 

Z 

Z 

z 

Z 

Z 

Z 

Z 

Z 

z 

Z 

Z 

be 

be 

bi) 

be 

bi) 

bi) 

be 

be 

be 

bi) 

bi) 

be 

bi) 

oe 

IL) 

V 

V 

0) 

(U 

4) 

0) 

OI 

0) 

01 

01 

4J 

0) 

Z 

z 

z 

Z 

z 

Z 

z 

Z 

Z 

Z 

Z 

Z 

z 

Z 

Pneumococcus 

bi) 

be 

be 

bi) 

bi) 

be 

be 

bi) 

bi) 

bi) 

bi) 

bi) 

bi) 

be 

ID 

V 

O) 

0) 

OI 

0) 

0) 

4) 

OI 

0) 

0) 

0) 

4) 

V 

Z 

Z 

Z 

Z 

z 

Z 

Z 

z 

z 

z 

Z 

z 

z 

Z 

Bacillus 

be  be 

bn 

be 

bi) 

bi) 

bi) 

be 

be 

bi) 

bi) 

be 

bi) 

be 

be 

Anthracis 

<u 

<u 

Z 

0) 

Z 

0) 

V 

OI 

V 

V 

4) 

4) 

01 

4) 

4J 

Z 

4J 

z 

Z 

Z 

z 

z 

Z 

Z 

z 

Z 

z 

Z 

Bacillus 

be  be 

be 

be 

be 

be 

bi) 

bi) 

bi) 

bi) 

bi) 

bi) 

bi, 

bi) 

be 

Prodigiosus 

IV 

V 

V 

Z 

V 

0) 

OI 

0) 

01 

Z 

4> 

01 

4) 

01 

Z 

Oi 

4J 

01 

'Z 

Z 

Z 

Z 

Z 

z 

Z 

Z 

z 

Z 

Z 

Bacillus 

be  be 

be 

be 

bi) 

be 

be 

bi) 

be 

be 

bi) 

be 

bi) 

be 

be 

Tvphosus 

V 

V 

Z 

0) 

Z 

0) 

0) 

OI 

01 

4) 

01 

0) 

o< 

V 

01 

V 

Z 

Z 

Z 

Z 

Z 

Z 

z 

Z 

z 

Z 

Z 

Z 

z 

Bacillus  Coli 

be  bi) 

bi) 

bi) 

be 

be 

be 

bi) 

be 

bi) 

bi) 

bi) 

bi) 

bi) 

be 

Communis 

V 

4; 

a; 

o> 

V 

0) 

0) 

01 

01 

4; 

01 

01 

Z 

01 

01 

Z 

4) 

Z 

Z 

z 

Z 

Z 

Z 

Z 

Z 

Z 

Z 

Z 

Z 

z 

* Mean  'I'empera- 

•^C<lCr2w^{ 

oooMoic<iPO' 

i-iot~»raoooooocoiMo 

ture 

GCOOOOoOC^OOt^t^l 

t>-  1 

CO  t-*  1 

t^CO  < 

ir-CO  1 

1 

1 

ir't'i 

t—  1 

t—  tr-  1 

0000 

« OS 

os 

OS 

OS 

OS 

OS 

OS 

os 

OS 

OS 

os 

os 

os 

os' 

Formaldehyde 
per  1,000  cubic 

c 

< 

< 

D <» 

L)  lU 

J o 

M 

01 

o 

<u 

U 

tn 

0) 

o 

OD 

V 

CJ 

in 

(U 

o 

in 

4) 

o 

cn 

0) 

u 

CO 

4> 

u 

in 

V 

u 

cn 

01 

u 

cd 

0) 

0 

in 

01 

0 

GQ 

V 

U 

feet 

G-  G 

G 

G 

G 

G 

G 

G 

G 

G 

a 

G 

G 

G 

G 

3 3 

G 

G 

G 

G 

G 

G 

G 

G 

G 

G 

G 

G 

G 

1 

0 o 

O 

O 

O 

O 

O 

O 

O 

0 

0 

0 

0 

0 

0 

S3 

M 

CM 

w 

CM 

(M 

w 

OJ 

S3 

w 

Ol 

S3 

N 

CM 

ec 

CO 

oo 

CO 

eo 

oo 

00 

00 

00 

00 

CO 

i 

OT3i3 

.3  . 

G O a 


2 >>  I >,  I >>o 

X^'OO'Oo'Go 
,G  -G  .G  . 
a o GO  a o c 


I >>  I 

0 730 
.G  . 
GOG 


.2 '^.2  >1.2  o.2o2^2k^2k^2^-2 
’ rt ■?  G ^ rt "2  rt "2  G 2:? G 


G 

>..2 
'O'G  lJ 
G^rzJ-G  rt+3  32  ca 
0-G2'G  Oi-G  OG  0) 


a2  aGi  a5  aGi  aGi  aGi  aGi  a2  a3 

*o  O ‘G  Ph  ’o  O *G  Oh  *u  *o  ^ *u  CJ  ’o  O Ij  &-J  *G  O ‘5  U ’G  O ‘G  O *o  U 'u  CU 
a>o><i^Da^a)4)a;a>a>a>a;a;a;a) 

XQhOhOhC-iD-iOmCLiCLiPhCLiCI^OhOmCGi 


Number  of 
experiment. 


M ?0 


Temperature  indicated  by  “ R ” is  the  temperature  of  the  room. 
Temperature  first  given  is  out  of  door  temperature. 

Neg.— No  growth. 


RESULTS  OF  EXPERIMENTS  AT  ORDINARY  TEMPER  AT  U RES- 


20 


Bacillus  Subtilis... 

be 

0) 

be 

(V 

Z 

bi) 

<u 

Z 

be 

<u 

Z 

be 

03 

z 

be 

03 

Z 

be 

03 

Z 

Neg. 

bi) 

03 

z 

be 

03 

z 

be 

03 

Z 

bi) 

03 

Z 

Neg. 

hi)  be 

03  03 

z z 

Staphy.  Pyogenes 

be 

(U 

bi) 

<u 

be 

(V 

bi) 

0) 

bo 

03 

bo 

03 

be 

03 

bi) 

03 

bi) 

03 

be 

03 

bi) 

03 

bi) 

03 

hi) 

03 

hi)  be 

03  03 

Z 

z 

Z 

z 

z 

Z 

z 

z 

z 

Z 

Z 

Z 

z z 

Staphy.  Pyogenes 
Aureus 

be 

be 

a; 

bi) 

<u 

bi) 

03 

be 

03 

be 

03 

be 

03 

bi) 

03 

bi) 

03 

be 

03 

bi) 

03 

bi) 

03 

be 

03 

z 

hi)  bi) 

03  03 

Z 

Z 

Z 

Z 

z 

Z 

Z 

Z 

Z 

Z 

z 

z z 

Staphy.  Pyogenes 

be 

D 

bi) 

a; 

bi) 

<u 

be 

03 

be 

03 

bi) 

03 

bi) 

03 

bi) 

03 

bi) 

03 

bo 

03 

bi) 

03 

bi) 

03 

bi) 

03 

be  ho 

03  03 

Z 

Z 

Z 

z 

z 

Z 

Z 

z 

z 

z 

Z 

Z 

z z 

be 

dj 

bi) 

<L» 

bi) 

a; 

be 

03 

bi) 

03 

bo 

03 

bi) 

03 

bi) 

03 

be 

03 

bi) 

03 

bi) 

03 

bi) 

03 

bi) 

03 

be  hi) 

03  03 

z 

Z 

z 

z 

z 

Z 

Z 

z 

z 

Z 

z 

Z 

Z Z 

Pneumococcus 

be 

<u 

be 

0) 

Z 

bi) 

a; 

Z 

bi) 

03 

z 

bi) 

03 

Z 

bi) 

03 

Z 

be 

03 

z 

bi) 

03 

Z 

bi) 

03 

Z 

bi) 

03 

Z 

bi) 

03 

z 

bi) 

03 

z 

be 

03 

Z 

hi)  hi) 

03  03 

Z Z 

Bacillus 

A nthraris 

be 

o> 

bi) 

<u 

bi) 

(U 

be 

03 

be 

03 

bi) 

03 

be 

03 

be 

03 

bi) 

03 

bi) 

03 

bo 

03 

bi) 

03 

bi) 

03 

ho  he 

03  03 

Z • 

Z 

z 

Z 

Z 

z 

z 

z 

z 

Z 

Z 

z 

Z Z 

Bacillus 

Prodigiosus 

be 

0) 

Z 

bi) 

(U 

Z 

bi) 

01 

Z 

bi) 

03 

Z 

bi) 

03 

z 

be 

03 

z 

bi) 

03 

z 

b£) 

<V 

z 

bi) 

03 

z 

bo 

03 

z 

be 

03 

z 

bi) 

03 

Z 

bi 

03 

Z 

be  bo 

03  03 

Z Z 

Bacillus 

Typhosus 

be 

<u 

Z 

be 

(L> 

bi) 

O) 

be 

03 

Z 

be 

03 

bi) 

03 

bi) 

03 

bi) 

03 

be 

03 

be 

03 

z 

bi) 

03 

bi) 

03 

hi) 

03 

bo  be 

03  03 

z 

Z 

Z 

Z 

z 

z 

Z 

Z 

z 

Z 

z z 

Bacillus  Coli 
Communis 

be 

<u 

bi) 

<u 

bi) 

0) 

bo 

03 

Z 

bo 

03 

z 

be 

03 

be 

03 

bi) 

03 

be 

03 

Z 

be 

03 

be 

03 

hi) 

03 

bi) 

o> 

bi)  be 

03  03 

Z 

z 

Z 

z 

Z 

z 

Z 

Z 

Z 

z 

z z 

* Mean  Tempera- 
ture   

tiH  pL|  b ^ b ;2h  {±4  h ^ b b 

t-<DOt-O?D<X>»rtC-00Okrte<lOe'lO'^i«O00C~05'rH«5C~OC0?D00C0 

W 

K 

cd 

Cei 

Pi 

Pi 

p:3 

Pi 

DS 

OS 

Formaldehyde 
per  1,000  cubic 
feet 

tn 

<u 

o 

a 

03 

0) 

o 

a 

03 

03 

O 

P 

93 

03 

03 

a 

S 

o 

P 

w 

03 

03 

C 

CD 

03 

03 

P 

X 

03 

03 

P 

m 

03 

03 

P 

CD 

03 

U 

a 

X 

03 

O 

a 

X 

03 

03 

C 

73 

03 

03 

P 

CD  03 

03  03 

O O 

a p 

3 

o 

CM 

p 

o 

o 

CM 

p 

o 

w 

P 

o 

P 

o 

«o 

P 

o 

O 

P 

o 

CD 

P 

o 

CD 

p 

o 

CD 

s 

<c 

CD 

P 

o 

CD 

P 

o 

CD 

p p 

o c 

CD  CD 

Number  of 
experiment 


C-1  CSl  CQ  04  C<l  C^3 


Temperature  indicated  by  “R  ” is  the  temperature  of  the  room. 
Temperature  first  given  is  out  of  door  temperature. 

Neg .— N o growth . 


21 


when  the  temperature  of  the  room  to  be  disinfected  is  60°  F.  or 
higher.  The  quantities  to  be  used  at  lower  temperatures  are  stated 
on  page  27. 

In  this  method  of  disinfection  the  following  rules  should  be 
observed : 

The  room  should  be  sealed  and  prepared  in  the  manner  described 
on  page  7. 

The  permanganate  (6f  oz.  for  each  1,000  cubic  feet  of  room  space) 
should  be  first  put  in  the  apparatus  or  generator. 

The  formaldehyde  solution  (16  oz.  for  each  1,000  cubic  feet  of  room 
space)  should  be  then  poured  on  the  permanganate. 

The  permanganate  must  go  in  first. 

As  the  formaldehyde  gas  is  promptly  liberated  by  the  vigorous 
chemical  reaction  of  the  formalin  and  the  potassic  salt,  and  rises  from 
the  container  in  an  immense  volume,  it  is  essential  that  all  prepara- 
tions be  made  in  advance,  and  that  the  operator  leave  the  room  at 
once  on  the  combination  of  the  two  chemicals.  The  door  or  window 
of  exit  should  be  promptly  closed  and  sealed,  and  the  room  left  closed 
for  six  hours. 

The  room  should  be  thoroughly  cleaned  after  disinfection.  All  out- 
of-the-way  places,  window  ledges,  mouldings,  etc.,  should  be  washed 
with  Standard  disinfectant  No.  3.  (See  page  28.)  The  fioors  of  the 
sick  room  should  receive  careful  attention,  and  the  solution  should 
wet  the  dust  and  dirt  in  the  cracks. 

The  Generator : — A few  words  as  to  the  generator  or  apparatus  re- 
quired in  this  method  of  disinfecting.  Whenever  practicable  the 
apparatus  described  on  page  16,  should  be  employed.  The  State 
Board  of  Health  recommends  that  health  officers  keep  a number  of 
these  on  hand  ready  for  immediate  use. 

When  this  apparatus  cannot  be  obtained,  use  can  be  made  of  a milk 
pail.  It  is  necessary  that  the  top  of  the  apparatus  flare  out  like  a 
funnel,  so  a milk  pail  should  be  selected.  The  pail  can  be  set  in  a 
pulp  or  wooden  bucket,  if  it  fits  snugly.  If  not  it  would  be  better  to 
tightly  wrap  the  sides  and  cover  the  bottom  with  two  layers  of  asbestos 
paper,  or,  if  this  cannot  be  got,  with  layers  of  blanket.  It  is 
absolutely  necessary  that  all  possible  heat  be  retained  in  the  ’ gener- 
ator, hence  the  necessity  for  a covering. 

Capacity  of  Generator — Care  must  be  taken  not  to  put  too  much 
of  the  formaldehyde  solution  in  the  generator.  Unless  this  precau- 
tion be  observed,  the  solution  will  boil  over  and  be  wasted,  besides 
causing  a possible  damage  where  it  falls. 

The  following  are  the  maximum  quantities  of  the  chemicals  which 
can  be  safely  used  in  the  containers  recommended  by  the  State 
Board  of  Health: 

Ten  or  12  quart  milk  pail — Formaldehyde,  16  oz. 

Permang-anate,  oz. 

Fourteen  quart  milk  pail — Formaldehyde,  24  oz. 

Permang-anate,  10  oz. 

Apparatus  on  pag-e  16  — Formaldehyde,  32  oz. 

Permanganate,  13  K oz. 


22 


FORMALDEHYDE  AND  POTASSIUM  PERMANGANATE 
METHOD  OF  DISINFECTION. 


Results  at  Low  Tempekatures. 

As  stated  in  the  first  edition  of  this  circular,  which  was  issued  at 
the  conclusion  of  the  experiments  in  practical  disinfection  undertaken 
in  1905,  it  had  been  the  experience  of  the  State  Board  of  Health  that 
formaldehyde,  however  generated,  often  failed  to  accomplish  satis- 
factory disinfection  if  used  at  a temperature  below  60°  F.  This  had 
been  the  personal  experience  of  the  secretary  in  1896-1897,  when  he 
tested  the  Robinson,  Moffatt,  Kny-Scherer  and  Hollister  lamps  and 
the  Trillat  and  the  Sanitary  Construction  Company’s  autoclaves,  con- 
stituting all  forms  of  apparatus  on  the  market  at  that  time.  In  these 
earlier  experiments  some  of  the  test  organisms  were  killed  when  tbe 
room  temperature  was  sufficiently  high,  but  there  was  uniform  growth 
of  cultures  when  the  temperature  was  below  60°  F.  It  then  appeared 
that,  as  with  chlorine,  the  germicidal  power  of  formaldehyde  was  in- 
creased by  high  temperature  and  was  materially  reduced  by  cold. 

These  early  results  were  confirmed  in  the  exhaustive  tests  made  by 
the  State  Board  of  Health  from  1898  to  1902,  and  it  was  then  appar- 
ent that  the  action  of  the  gas  was  modified  not  only  by  temperature 
and  humidity,  but  by  some  other  factors  not  fully  understood. 

While  tbe  experimental  work  of  the  State  Board  of  Health  of  1898- 
1902  led  to  the  establishment  of  a method  of  formaldehyde  disinfec- 
tion which  was  satisfactory  under  ordinary  conditions  (See  p.  14), 
many  of  the  problems  of  aerial  disinfection  with  formaldehyde  re- 
mained unsolved.  Neither  the  question  of  proper  temperature  nor 
of  proper  humidity  could  be  satisfactorily  settled,  and  as  the  majority 
of  investigators  adhered  to  the  belief  that  disinfection  with  formalde- 
hyde was  impracticable  at  low  temperature,  the  Illinois  State  Board 
of  Health  deemed  it  the  part  of  wisdom  to  advise  the  use  of  sulphur 
at  any  temperature  below  60°  F. 

It  might  be  appropriately  stated  here,  that  in  the  279  experiments 
conducted  by  the  Maine  State  Board  of  Health,  the  temperatures 
varied  from  67°  F.  to  80°  F. 

It  would  appear  in  the  light  of  the  results  of  the  experiments  under- 
taken in  1906  by  the  Illinois  State  Board  of  Health,  that  successful 
disinfection  with  formaldehyde  is  not  so  much  a question  of  either 
temperature  or  humidity  as  one  of  the  proper  method  of  the  genera- 
tion of  the  gas.  The  results  of  the  most  recent  experiments  are  tab- 
ulated on  page  25,  and  these  show  that  as  satisfactory  results  were 
obtained  at  a temperature  of  20°  below  the  freezing  point  as  at  mid- 
summer heat;  and  on  seemingly  unfavorable  days  as  on  those  when 
perfect  disinfection  might  be  looked  for. 


23 


These  facts  were  clearly  demonstrated  in  the  first  fifteen  of  the  re- 
cent experiments,  (Experiments  Nos.  1 to  le5,  page  25)  in  which  the 
ordinary  bacterial  tests  were  carried  out  with  the  utmost  accuracy  by 
two  thoroughly  competent  bacteriologists,  who  personally  superin- 
tended every  detail  of  the  work,  from  the  preiDaration  of  the  cultures 
to  the  final  laboratory  examination,  including  the  preparation  of  the 
test-room  and  the  generation  of  the  formaldehyde  gas.  The  final 
tests  (Experiments  1-5,  page  26),  show  results  that  are  even  more 
convincing  and  gratifying,  as  in  these  experiments  the  gas  was  put  to 
the  severest  disinfecting  tests  suggested  from  any  quarter. 

For  the  purposes  of  experimental  disinfection,  an  ordinary  office 
room  having  a capacity  of  3,500  cubic  feet  was  secured.  This  room 
contained  two  large  windows  and  one  door,  and  these,  fitting  rather 
snugly,  were  not  sealed  in  any  of  the  tests.  In  the  first  fifteen  ex- 
periments, strips  of  bibulous  (milk)  paper  saturated  with  twenty-four 
hour  bouillon  cultures  were  used,  and  exposed  at  various  heights  in 
different  parts  of  the  room.  These  slips  were  kept  in  the  room  for  six 
hours  during  the  liberation  of  the  formaldehyde  gas  and  were  then 
taken  to  the  laboratory  in  tubes  of  sterile  bouillon.  These  tubes,  to- 
gether with  tubes  inoculated  with  control  culture  slips,  which  were 
used  in  every  instance,  were  then  placed  in  the  incubator  for  a period 
of  forty-eight  hours.  It  may  be  noted  that  bacteria  of  the  most  re- 
sistant character  were  used,  and  further,  that  cultures  made  from 
the  control  slips  invariably  showed  profuse  and  healthy  bacterial 
growths. 

The  almost  entirely  uniform  residts  of  these  experiments,  consisting 
of  80  culture  tests,  taken  with  the  290  culture  tests  made  in  1905, 
indicate  conclusively  that  we  now  have,  in  the  potassium  permanga- 
nate-formaldehyde method  of  disinfection,  one  which  is  easily  ap- 
plied, which  is  of  almost  nominal  expense,  and  one  upon  which  we 
may  place  dependence  at  all  times  and  under  all  conditions. 

That  the  method  should  be  subjected  to  the  severest  tests  however, 
an  effort  was  made  to  ascertain  those  conditions  which,  in  the  opinion 
of  competent  observers,  were  liable  to  lead  to  failure  or  to  unsatisfac- 
tory results  in  practical  disinfection,  and  the  final  tests  shown  on 
page  26  were  made  under  those  conditions.  Various  writers  had 
questioned  the  power  of  formaldehyde  to  penetrate  cloth,  hangings  or 
drapings ; others  had  doubted  the  disinfecting  powers  of  formaldehyde 
on  articles  in  the  lower-most  parts  of  the  room,  especially  when  cov- 
ered with  carpet  or  matting.  Dr.  Hibbert  Winslow  Hill,  of  the  Min- 
nesota State  Board  of  Health  Laboratories  had  cited  (^')  as  sources  of 
error  in  testing  gaseous  disinfectants,  the  following  points:  (a)  That 

freshly  dried  bacterial  cultures  are  more  highly  resistant  than  moist 
specimens  or  those  dried  a week  or  more.  (5)  That  freshly  dried 
specimens  (24,  48,  72  and  96  hours),  particularly,  if  dried  on  hard  ma- 
terial are  especially  resistant. 

It  will  be  noted  that  in  the  final  group  of  experiments  this  method 
of  disinfection  was  subjected  to  the  severest  tests  under  most  un- 
favorable conditions,  but  in  spite  of  this  the  results  differed  little  if 


'The  Journal  of  Infectious  Diseases.  Sup.  No.  2,  February,  1906,  page  210. 


24 


at  all  from  the  former  tests.  Hard- wood  butchers’  skewers  were  used 
in  all  of  the  final  tests  as  well  as  milk  paper  slips  and  the  cultures  on 
these  skewers  and  slips  were  dried  24,  48,  72  and  96  hours.  The  re- 
sults were  eminently  satisfactory.  The  results  with  the  freshly  dried 
specimens,  dried  on  hard  material,  were  remarkable  when  we  consider 
that  the  exceedingly  resistant  bacilli  {B.  anthracis  and  B.  suhtilis) 
failed  to  survive. 

The  paper  slips  were  placed  under  carpets  and  others  wrapped  in 
four  or  five  layers  of  fiannel,  and  while  the  results  in  these  tests  were 
not  all  negative  they  were  such  as  to  indicate  that  formaldehyde  gas, 
properly  generated,  has  greater  penetrating  power  than  formerly  be- 
lieved. The  only  absolute  failures  in  disinfection  were  in  those  tests 
in  which  culture  slips  were  placed  between  the  leaves  of  books,  and, 
in  such  instances,  bacterial  destruction  could  not  reasonably  be  looked 
for. 

These  results  certainly  corroborate  the  previous  findings  of  the 
State  Board  of  Health. 

Quantities  of  Chemicals'. — In  view  of  the  difficulties  heretofore  at- 
tendant upon  efforts  made  to  secure  satisfactory  disinfection  at  low 
temperatures,  it  was  thought  advisable  to  use  in  all  cases  the  maxi- 
mum amount  of  formaldehyde  employed  in  previous  experiments. 
(See  page  19).  Through  an  error  of  calculation,  however,  made  after 
the  completion  of  the  second  test,  the  amounts  were  diminished,  but, 
as  will  be  noted,  the  results  were  unchanged.  Whether  success  would 
have  been  attained  had  the  amounts  used  been  further  decreased,  it 
is  impossible  to  say.  However,  a further  decrease  is  not  necessitated 
for  reasons  of  economy  nor  can  it  be  recommended.  The  quantities 
of  formaldehyde  and  potassium  permanganate  to  be  used  at  varying 
temperatures  are  set  forth  on  page  27. 


“The  true  principle  of  disinfection  is  to  attack  the  specific  poisons  of 'disease 
at  their  seats  of  origin  as  far  as  these  are  accessible  to  us.” — N otter- Hoiirocks. 

“It  is  a maxim  universally  agreed  upon  in  agriculture,  that  nothing  must 
be  done  too  late;  and  again,  that  everything  must  be  done  at  its  proper  season, 
while  there  is  a third  precept  which  reminds  us  that  opportunities  lost  can 
never  be  regained,” — Pliny. 


Formaldehyde — Potassium  Permanganate  Method. 


25 


Control 


Staph,  pyogenes 
aureus 


Staph,  pyogenes 
albus 


Bacillus  prodigiosus. 


OTXOJOTOTMWCDOOOTCOMCOOTa) 

OOOOOOOOOOOOOOO 

PnPH^P-lPHPHQ-ipHP-lpHQ-lPHO-iPHP-l 


Ibchchrtictxbrhchfifcicta) 

.<J.»D<UDD4i!]JDl>C3 


ZZZZZ 


.•bctictjsticbcbctxbchtbc 

:ZZZZZZZZZZ 


Bacillus  coli  communis, 


Bacillus  typhosus , 


Bacillus  subtilis. 


Bacillus  anthracis. 


Formaldehyde,  per 
1,000  cubic  feet 


Precipitation  in  inches. 


Vapor  pressure. 


Relative  humidity. 


o . 

o >> 


Mean  temperature  day 
outdoors 


Temperature  of  room- 
ending 


Temperature  of  room- 
beginning  


Number  of  experiment. 


; iy;  tx  be  he  be  be  be  be.2  he 
. (U  K (U  0)  oj  <u  <u  <u;t; 

IZZZZZZZZ^Z 


bebebetxbcbebebcbeoebcbebebebo 

ZZZZZZZZZ2ZZZZZ 


bebebebebebcbflbebebebebe bex!  be 

zzzzzzzzzzzzz^z 


bebebebebcbcbebebcbebe'oc be.G  be 

zzzzzzzzzzzzz^z 


O O 0^0^  O O O O ^ CO  rH  CO  o 


> CO  05  t- 00  CO 


1— K00-^'^C~'^00055 
-i<COtr-r~>OCOOOC<loOOj'^ao-t<« 
OOOOO-'i-nMOOi-lOOi 


T3  .T3'a 
0 • a 3 

o ;^o 
"u  ■'o’o 


a.uuaHUUUaHU^(:SucuUU 


iHWC0'^irDCDt--00C5O^WC0"^U^ 


Formaldehyde — Potassium  Permanganate  Method. 


26 


to 

55 

W 


u 

w 

Oh 

Q 

W 


X 

w 

o 

EO 

H 

D 

W 

Di 


Specimens  dried— (in 
hours.) 


Controls 


C0U3X  XXX  XX  x’  xxx’ 

^-1  t-. 

3DD  D33  333  333 

OOO  OOO  OOO  OOO 

.3X242  4242X2  42  X242  424242 

oooooo  «o?oeo 

oaoaoa 


xxx  xxx  xxx  xxx  xxx 

OOO  OOO  OOO  OOO  OOO 

(X&hPui  CLiCLieL,  CLhOhCl,  OuiPuiDl,  £I,PLhPh 


Staphy,  pyogenes 
aureus 


ZZ 


X2  tiC  42  1 !2D 

.Mi)  M.  . 4) 

Ox  O ;x 


Bacillus  prodigiosus. 


iic  he  ; be 

i»  .M  . aj 

ZZ  O :Z 


x2  he  42  : he 
(1>  ^ . o 

Oz  o :Z 


£2? 

Oz 


Bacillus  coli  communis 


he  he  x2  ; he 

4)  i)  — . 41 

ZZ  o :z 


5^  £ 

Oz  O :z 


he  ho 

4>  4> 

ZZ 


Bacillus  typhosus  . 


he  he  x2  I he 

4)  4;  M>  . 4) 

ZZ  o ;z 


ZZ  O 


Bacillus  subtilis. 


42  he  x2  1 he 
.M  4>  . o 

Oz  O :Z 


42  ho  x: 
<u  *- 

Oz  O 


Bacillus  anthracis. 


hchc  X 

4J  4) 

ZZ  o 


x:  be  ^ 

4-»  0/ 

Oz  o 


ZZ 


i - 


Precipitation  in  inches. 


W rt  i2 
4ij  O 41 
O M ^ 

42t24s; 

£2  5“ 

T2 
QO  Ol  O 

cuao 


* tn 

■§ll 

3 “ 


M 1) 


22  42  XD 


ill 


o X 

■,T2 


.t2.5‘  o .2-  c ° .ir  3 o .tr  3 ° 


C ^ X 

23 


Vapor  pressure . 


Relative  humidity. 


Mean  temperature  of 
day  out  doors 

Temperature  of  room- 
ending  

Temperature  of  room- 
beginning 


) Number  of  experiment. 


Note— In  the  foregoing  experiments  24  ounces  of  formaldehyde  solution  were  used  to  each  1,000  cubic  feet  of  air  space. 


27 


Final  Recommendations. 

The  Illinois  State  Board  of  Health  now  recommends  formaldehyde 
as  an  aerial  disinfectant,  when  used  in  combination  with  potassium 
permanganate,  in  the  manner  described  in  this  circular. 

The  following  quantities  of  chemicals  should  be  used  for  each 
1,000  cubic  feet  of  air  space: 

Temperature  above  60°  F. — Formaldehyde  (40%),  16  ounces. 

Potassium  permanganate  6%  ounces. 

Temperature  below  60°  F. — Formaldehyde  (40%)  24  ounces. 

Potassium  permanganate  10  ounces. 

The  following  suggestions  are  important  and  may  prevent  failure 
in  the  application  of  this  method  of  disinfection. 

1.  Good  formaldehyde  is  essential  to  success.  Reliable  formal- 
dehyde or  formalin  is  not  very  expensive;  poor  formaldehyde  is  dear 
at  any  price.  (See  remarks  on  pages  14  and  18.)  Get  the  best! 

2.  The  permanganate  of  potassium  must  be  in  powdered  form,  or 
in  long  needle  shaped  crystals.  If  the  large  octahedral  crystals  are 
purchased,  they  must  be  powdered  before  use.  Get  the  best! 

3.  The  retention  of  the  heat  caused  by  the  reaction  of  the  com- 
bined chemicals  is  necessary  to  the  generation  of  a large  volume  of 
gas.  Hence  it  is  necessary  that  the  metal  container  or  generator  be 
covered  with  asbestos,  or  with  a non-conductive  outer  vessel. 

4.  As  the  union  between  the  chemicals  causes  much  frothing  and 
effervesence,  large  vessels  are  necessary  to  prevent  the  solution  from 
running  over.  The  amounts  of  the  chemicals  set  forth  on  page  21 
should  never  be  exceeded  in  vessels  of  the  size  mentioned. 

5.  The  formaldehyde  solution  must  be  poured  upon  the  potassium 
permanganate.  The  potassium  permanganate  must  not  be  dropped 
into  the  formaldehyde'.  (See  page  21.) 

6.  The  room  should  be  sealed  so  as  to  prevent  the  escape  of  gas. 
(See  page  7.) 

7.  Clothing,  bedding,  etc.  must  be  treated  as  described  on  page  7. 

8.  It  is  always  well  to  wash  the  wood  surfaces  of  the  room,  as  de- 
scribed on  page  7.  It  is  absolutely  necessary  to  do  so  when  such 
surfaces  have  been  soiled  by  the  sputum  or  any  other  discharges  of 
the  patient. 

9.  It  is  not  practicable  to  disinfect  books  with  formaldehyde. 

In  conclusion,  the  State  Board  of  Health  earnestly  advises  and 
urges  health  officials,  physicians  and  all  others  who  may  be  called 
upon  to  perform  disinfection,  to  adopt  the  method  of  aerial  disinfec- 
tion recommended  herein,  and  to  abandon  the  use  of  all  other 
methods. 

Published  by  order  of  the  State  Board  of  Health. 

James  A.  Egan,  M.  D.,  Secretary. 

June  1.  1906. 


28 


STANDARD  DISINFECTANTS. 


The  following  are  simple,  cheap  and  most  reliable  Disinfectants: 

Standard  Disinfectant  No.  1. 

Four  per  cent  Solution  of  Chloride  of  Lime. 

Dissolve  Chloride  of  Lime  of  the  best  quality,  in  water,  in  proportions  of  six 
ounces  of  lime  to  one  gallon  of  ivater. 

This  is  one  of  the  strongest  disinfectants  known.  Discharges  from  the 
bowels  of  a patient  suffering  from  a contagious  or  infectious  disease,  should 
be  received  in  a vessel  containing  this  solution,  and  allowed  to  stand  for  an 
hour  or  more  before  being  thrown  into  the  vault  or  water  closet.  Discharges 
from  the  throat  or  lungs  should  be  received  in  a vessel  containing  this 
solution. 

Chloride  of  Lime  in  powder  may  be  used  freely  in  privy  vaults,  cess  pools, 
drains,  sinks,  etc. 

Instead  of  the  solution  of  chloride  of  lime,  carbolic  acid  may  be  used  for 
the  same  purposes,  in  a strength  of  63^  ounces  to  the  gallon  of  water.  This 
makes  a five  per  cent  solution  of  carbolic  acid. 

Standard  Disinfectant  No.  3. 

Bichloride  of  Mercury,  1-500. 

Dissolve  Corrosive  Sublimate  and  Muriate  of  Ammonia  in  water,  in  the  propor- 
tion of  two  drachms  {120  grams — ounce)  of  each  to  the  gallon  of  water.  Dis- 
solve in  a wooden  tub,  ban  el  or  an  earthen  crock. 

Use  for  the  same  purpose  and  in  the  same  way  as  No.  1.  Equally  effective 
but  slower  in  action,  so  that  it  is  necessary  to  let  the  mixture  (disinfectant 
and  infected  material)  stand  about  four  hours  before  disposing  of  it.  This 
solution  is  odorless,  while  the  chloride  of  lime  solution  is  often  objectionable 
in  the  sick  room  on  account  of  its  smell. 


Standard  Disinfectant  No.  3. 

Bichloride  of  Mercury,  1-1000. 

Dissolve  one  drachm  {60  grains — 3^  ounce)  each  of  Corrosive  Sublimate  and 
Muriate  of  Ammonia  in  one  gallon  of  water.  Dissolve  in  a wooden  tmh,  barrel 
or  pail  or  earthen  crock. 

Used  for  the  disinfection  of  soiled  underclothing,  bed  linen,  etc.  Immerse 
the  articles  for  four  hours,  then  wring  them  out  and  boil  them.  This  solution 
is  excellent  for  wetting  the  floors  of  offices,  stores,  workshops,  halls  and 
school  rooms  before  sweeping. 

Mixed  with  an  equal  quantity  of  water  this  solution  is  useful  for  washing 
the  hands  and  general  surfaces  of  the  bodies  of  attendants. 

Chloride  of  lime,  carbolic  acid  and  corrosive  sublimate  are  deadly  poisons. 

Milk  of  Lime  {Quicklime). 

Slack  a quart  of  freshly-burnt  lime  {in  small  pieces)  with  three-fourths  of  a 
quart  of  water — or,  to  be  exact,  60  parts  of  water  by  weight  ivith  100  of  lime.  A 
dry  powder  of  slack  lime  {hydrate  of  lime)  results.  Make  milk  of  lime  not  long 
before  it  is  to  be  used  by  mixing  one  part  of  this  dry  hydrate  of  lime  with  eight 
parts  {by  weight)  of  ivater. 

Air  slacked  lime  is  worthless.  The  dry  hydrate  may  be  preserved  some 
time  if  it  is  enclosed  in  an  air-tight  container.  Milk  of  lime  should  be  freshly 
prepared,  but  may  be  kept  a few  days  if  it  is  closely  stoppered. 

Quicklime  is  one  of  the  cheapest  of  disinfectants.  This  solution  can  take 
the  place  of  chloride  of  lime,  if  desired  It  should  be  used  freely,  in  quantity 
equal  in  amount  to  the  material  to  be  disinfected.  It  can  be  used  to  white- 
wash exposed  surfaces,  to  disinfect  excreta  in  the  sick  room  or  on  the  surface 
of  the  ground,  in  sinks,  drains,  stagnant  pools. 


I 


29 


ADDENDA. 

(Do  not  in  any  manner  modify  the  “Final  Recommendations”  on  pag-e  27.) 


While  the  foregoing  circular  on  “Practical  Disinfection”  was  in 
press,  the  Secretary  submitted  the  proof  sheets  containing  the  an- 
nouncement of  results  of  the  experiments  with  the  formaldehyde- 
potassium  permanganate  method,  to  a prominent  bacteriologist  who 
had  previously  manifested  great  interest  in  the  workings  of  the  State 
Board  of  Health,  and  requested  that  he  examine  into  the  technique 
followed  in  the  experiments,  not  only  in  the  laboratory  but  in  the 
apartment  in  which  disinfection  was  attempted,  and  pass  an  opinion 
on  the  same  and  the  results  obtained.  This  gentleman  offered  no 
criticism  on  the  process  followed,  but  while  expressing  the  belief  that 
the  method  of  disinfection  recommended  was  dependable  at  all  times, 
he  strongly  advised  that  further  experiments  be  conducted  in  order 
to  definitely  determine  whether  the  growth  of  the  cultures  exposed 
had  not  been  simply  inhibited.  He  cited  experiments  made  by  other 
sanitary  authorities  in  which  it  was  reported  that  no  growth  was  found 
until  after  the  seventh  day,  when  the  growth  was  abundant.  ' In  short, 
he  inclined  to  the  view  that,  possibly  the  exposed  cultures  which  had 
been  kept  in  the  incubator  for  two  days  (see  pages  17  and  2^)  had  not 
been  killed,  that  the  growth  had  merely  been  retarded;  that  if  the 
cultures  had  been  kept  in  the  incubator  for  ten  days  instead  of  two 
the  results  might  have  been  different. 

The  Secretary  immediately  laid  the  matter  before  another  bacter- 
iologist equally  prominent  and  requested  an  opinion,  which  was  given 
in  the  following  terse  remarks: 

A true  growth  appears  in  one  or  two  days  as  a rule.  Never  heard  of  a 
growth  at  ten  days.  An  inhibited  growth  is,  in  practical  effect,  no  growth. 
Moulds  are  not  growths.  Contamination  is  too  often  mistaken  for  a growth. 

We  believe  that  the  gentleman  last  quoted  struck  the  key  note 
when  he  said  “an  inhibited  growth  is,  in  practical  effect,  no  growth.” 

Rosenau  probably  entertained  the  same  opinion  when  he  said  in 
his  work  on  Disinfection  and  Disinfectants : 

As  a matter  of  fact  it  is  not  necessary  actually  to  destroy  the  infective 
agents;  it  is  quite  sufficient  to  render  them  incapable  of  causing  or  conveying 
disease.  For  example,  if  the  micro-organisms  are  so  attenuated  that  they 
have  lost  their  virulence,  or  if  they  are  so  scattered  that  they  are  too  few  to 
cause  infection,  the  object  of  disinfection  has  been  accomplished. 

While  feeling  assured  that  a growth  in  the  incubator,  in  which  all 
conditions  were  favorable,  would  not  necessarily  indicate  the  survival 
of  bacteria  in  the  infected  room  in  which  many  conditions  were  un- 
favorable; that  a retarded  growth  in  the  incubator  would  indicate 
“organisms  so  attenuated  that  they  have  lost  their  virulence;”  that 


30 


such  organisms,  if  existing  in  the  infected  room  after  disinfection, 
would  have  their  activity  destroyed  by  free  exposure  to  currents  of 
fresh  air  and  possible  sunlight,  to  say  nothing  of  the  housewife’s  mop 
and  broom ; the  Secretary  resolved  to  follow  the  recommendation  made 
and  conduct  further  experiments,  in  order  to  determine  whether  the 
growth  of  the  cultures  had  not  been  simply  inhibited,  and  gave  direc- 
tions that  the  publication  of  this  circular  be  delayed. 

The  following  is  an  epitomized  account  of  the  experiments  con- 
ducted under  the  direct  supervision  of  the  Secretary  and  Assistant 
Secretary : 

Experiment  Number  1,  June  30,  1906. 

Bacteriologists,  Dr.  H.  C.  Blankmeyer  and  Mr.  W.  J.  Hoyt. 

Room  3,500  cubic  feet,  as  in  previous  experiments.  Formaldehyde,  24  ounces 
per  1,000  cubic  feet.  Temperature,  75°F.  Relative  humidity,  56%.  Room 
kept  closed  for  six  hours. 

Test  organisms,  B.  anthracis,  B.  coli  com.,  B.  typhosis  and  S.  pyogenes 
aureus,  freshly  dried  specimens  on  skewers  and  slips.  Laboratory  technique 
as  on  page  23.  Ten  days  period  of  incubation. 

No  growth.  Contamination  in  some  tubes. 


Experiment  Niimbep.  2,  Jury  2,  1906. 

Bacteriologists,  Dr.  H.  C.  Blankmeyer  and  Mr.  W.  J.  Hoyt. 

Room  as  in  Experiment  number  1.  Formaldehyde,  16  ounces  per  1,000  cubic 
feet.  Temperature  76° F.  Relative  humidity,  58%.  Room  kept  closed  for  six 
hours. 

Test  organisms,  laboratory  technique  and  incubation  as  in  Experiment  num- 
ber 1. 

No  growth.  Contamination  in  some  tubes. 


ExperIxMent  Number  3,  July  9,  1906. 

BcLCtet'iologists,  Dr.  H.  C.  Blankmeyer  and  Mr.  W.  J.  Hoyt. 

Cold  storage  warehouse.  Room  capacity,  2,500  cubic  feet.  Formaldehyde, 
32  ounces  per  1,000  cubic  feet.  Temperature  38°F.  Relative  humidity,  78%. 
Room  kept  closed  for  six  hours. 

Test  organisms,  laboratory  technique  and  period  of  incubation  as  in  Experi- 
ment number  1. 

No  growth.  Contamination  in  a few  tubes. 


Experiment  No.  4,  July"  11,  1906. 

Bacteriologists,  Dr.  H.  C.  Blankmeyer  and  Mr.  W.  J.  Hoyt. 

Cold  storage  warehouse.  Room  as  in  Experiment  No.  3.  Formaldehyde 
24  oz.  per  1,000  cubic  feet.  Temperature  38°  F.  Relative  humidity  85%. 
Room  kept  closed  for  6 hours. 

Test  organisms,  laboratory  technique  and  period  of  incubation  as  in  Ex- 
periment No.  1. 

No  growth.  Contamination  in  some  tubes. 


31 


Expekiment  No.  5,  July  16,  1906. 

Bacteriologists,  Dr.  H.  C.  Dlankmeyer  and  Mr.  W.  J.  Hoyt. 

Room  as  in  Experiment  No.  1.  Formaldehyde  24  oz.  per  1,000  cubic  feet. 
Temperature  72°  P.  Relative  humidity  59%.  Room  kept  closed  for  6 hours. 

Test  organisms,  laboratory  technique  and  period  of  incubation  as  in  Ex- 
periment No.  1. 

No  growth. 


Experiment  No.  6,  July  17,  1906. 

Bacteriologists,  Dr.  H.  C.  BUmkmeyer,  Mr.  W.  J.  Hoyt  and  Dr.  W.  H.  Buhlig. 

Room  as  in  Experiment  No.  1.  Formaldehyde  16  oz.  per  1,000  cubic  feet. 
Temperature  of  room  68°  P.  Relative  humidity  79%.  Room  kept  closed  for 
6 hours. 

Test  organisms,  B.  anthracis,  B.  coli  com.,S.  pyogenes  aureus.  Freshly 
dried  specimens  on  skewers  and  slips.  Laboratory  technique  as  on  page  23. 
Incubation  8 days.  Results: 

. B.  anthracis.  No  growth. 

S.  pyogenes  aureus.  No  growth. 

B.  coli  com.  Slight  growth  (questionable). 

Dr.  Buhlig,  who  was  called  from  Chicago  to  assist  in  these  experiments, 
devoted  several  days  time  to  the  examination  of  the  cultures  and  controls 
used  in  Experiment  No.  6. 


Experiment  No.  7,  August  5,  1906. 

Bacteriologists  Dis.  W.  H.  Buhlig  and  H.  C.  Blankmeyer. 

Room  as  in  Experiment  No.  1.  Formaldehyde  24  oz.  per  1,000  cubic  feet. 
Temperature  80°  F.  Relative  humidity  76%.  Room  kept  closed  for  six 
hours. 

Test  organisms  B.  anthracis,  B.  coli  com.  B.  typh.  B.  diphtheria  and  S. 
pyogenes  aureus,  freshly  dried  specimens,  (24,  48,  72  and  96  hours)  dried  on 
skewers  and  slips  of  milk  paper,  also  skewers  and  papers  freshly  dipped. 
Uninoculated  slips  and  skewers  were  also  exposed  to  the  action  of  the  gas  in 
the  room,  and  inserted  in  freshly  infected  bouillon  tubes  to  determine 
whether  the  absorbed  formaldehyde  could  in  any  manner  influence  the 
results.  All  possible  aseptic  precautions  were  taken  to  insure  correct  inter- 
pretations. Period  of  incubation  eleven  days. 

No  growth. 


Experiment  No.  8,  August  6,  1906. 

Bacteriologists  Drs.  W.  H.  Buhlig  and  H.  C.  Blankmeyer. 

Room  as  in  Experiment  No.  1.  Formaldehyde  16  oz.  per  1,000  cubic  feet. 
Temperature  78°  F.  Relative  humidity  76%.  Room  kept  closed  for  six  hours. 

Test  organisms  and  laboratory  technique  as  in  Experiment  No.  6.  Period 
of  incubation  twelve  days. 

No  growth. 


Experiment  No.  9,  August  12,  1906. 

Bacteriologist  Dr.  H.  C.  Blankmeyer. 

Room  as  in  Experiment  No.  1.  Formaldehyde  16  oz.  per  1,000  cubic  feet. 
Temperature  76°  F.  Relative  humidity  54%.  Room  kept  closed  for  six  hours. 

Test  organisms  and  laboratory  technique  as  in  Experiment  No.  6.  Period 
of  incubation  ten  days.  Results,  no  growth  except  in  case  of  S.  pyog.  aureus 
on  seventy-two  hour  slips  only. 


university  OF  ILLINOIS- 


32 


Expkeiment  No.  10,  August  29 

Bacteriologists  Drs.  H.  C.  Blankmeyer  and  W,  O.  Bain. 

Room  as  in  Experiment  No.  1.  Formaldehyde  16  oz.  per  1,000  cubic  feet. 
Temperature  72°F.  Relative  humidity  56%.  Room  kept  closed  for  six  hours. 

Test  organisms  B.  anthracis  and  B.  subtilis,  freshly  dried  specimens  (24,  48, 
72  and  96  hours)  dried  on  skewers  and  slips  of  milk  paper,  also  skewers  and 
papers  freshly  dipped.  Period  of  incubation  four  days. 

No  growth.  All  control  tubes  showed  growth  except  skewers  of  anthrax 
dried  ninety-six  hours. 


In  all  experiments,  an  examination  of  the  controls  was  made  to  con- 
firm the  growth  of  the  microorganisms. 

Seven  hundred  and  ninety-four  test  objects  were  exposed  in  Exper- 
iments Nos.  1 to  10. 

It  will  be  noted  that  in  Experiment  No.  9 the  most  resistant  bacilli 
{B.  anthracis  and  B.  subtilis)  only  were  used.  The  fact  that  these 
were  uniformly  killed  would  alone  almost  conclusively  prove  the  effi- 
cacy of  this  method  of  disinfection. 

In  View  of  the  results  obtained  in  the  foregoing  experiments  and  in 
the  fifty  previously  conducted,  the  Illinois  State  Board  of  Health 
again  recommends  formaldehyde  as  an  aerial  disinfectant  when  used 
in  combination  with  potassium  permanganate  in  the  method  described 
in  this  circular.  The  State  Board  of  Health  also  unhesitatingly  pro- 
nounces this  method  of  disinfection,  one  on  which  dependence  can  be 
placed  under  all  conditions  of  temperature  and  humidity. 

James  A.  Egan,  M.  D. 

September  10, 1906.  Secretary. 


“Indeed,  what  is  there  that  does  not  appear  marvellous  when  it  comes  to 
our  knowledge  for  the  first  time?  How  many  things,  too,  are  looked  upon  as 
quite  impossible  until  they  have  been  actually  effected?”— Ptmiy. 


